Inhibition of acyl-coenzyme A:cholesterol acyltransferase stimulates cholesterol efflux from macrophages and stimulates farnesoid X receptor in hepatocytes
Experimental & Molecular Medicine
;
: 407-417, 2008.
Artículo
en Inglés
| WPRIM
| ID: wpr-171132
ABSTRACT
We investigated the mechanism of spontaneous cholesterol efflux induced by acyl-coenzyme Acholesterol acyltransferase (ACAT) inhibition, and how an alteration of cholesterol metabolism in macrophages impacts on that in HepG2 cells. Oleic acid anilide (OAA), a known ACAT inhibitor reduced lipid storage substantially by promotion of cholesterol catabolism and repression of cholesteryl ester accumulation without further increase of cytotoxicity in acetylated low-density lipoprotein-loaded THP-1 macrophages. Analysis of expressed mRNA and protein revealed that cholesterol 7alpha-hydroxylase (CYP7A1), oxysterol 7alpha- hydroxylase (CYP7B1), and cholesterol 27-hydroxylase (CYP27) were highly induced by ACAT inhibition. The presence of a functional cytochrome P450 pathway was confirmed by quantification of the biliary cholesterol mass in cell monolayers and extracelluar medium. Notably, massively secreted biliary cholesterol from macrophages suppressed the expression of CYP7 proteins in a farnesoid X receptor (FXR)-dependent manner in HepG2 cells. The findings reported here provide new insight into mechanisms of spontaneous cholesterol efflux, and suggest that ACAT inhibition may stimulate cholesterol-catabolic (cytochrome P450) pathway in lesion-macrophages, in contrast, suppress it in hepatocyte via FXR induced by biliary cholesterol (BC).
Texto completo:
Disponible
Índice:
WPRIM (Pacífico Occidental)
Asunto principal:
Factores de Transcripción
/
Bilis
/
Ácidos Oléicos
/
Regulación Enzimológica de la Expresión Génica
/
Células Cultivadas
/
Colesterol
/
Esterol O-Aciltransferasa
/
Ésteres del Colesterol
/
Receptores Citoplasmáticos y Nucleares
/
Hepatocitos
Tipo de estudio:
Estudio pronóstico
Límite:
Humanos
Idioma:
Inglés
Revista:
Experimental & Molecular Medicine
Año:
2008
Tipo del documento:
Artículo
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